Nanoparticle Compositions Providing Enhanced Color for Cosmetic Formulations

ABSTRACT

The present invention relates to cosmetic, dermatological, and pharmaceutical compositions that deliver, in an acceptable vehicle or carrier comprising a film former or wax and an effective amount of nanoparticles and one or more pigments and methods for improving the appearance of a biological surface by altering the optical properties of the biological surface. The compositions of the invention enhance color and may be topically applied to the biological surface in an amount effective in improving the aesthetic and natural appearance of the biological surface.

FIELD OF THE INVENTION

The present invention generally relates to cosmetic, dermatological, andpharmaceutical compositions and their use. More particularly the presentinvention relates to cosmetic compositions and their use in improvingthe appearance of biological surfaces.

BACKGROUND OF THE INVENTION

Modern skin care formulations must meet high standards of efficacy, skincompatibility and aesthetic appeal. Consumers are interested inmitigating or delaying the dermatological signs of chronologically-aged,hormonally-aged or photo-aged skin, such as fine lines, wrinkles,drying, and sagging skin, and other conditions due to a progressivedegradation of the skin matrix. Consumers are interested in improvingthe appearance of, for example, skin, lips, nails, and hair by impartingto these biological surfaces a certain color, which would ideallyproduce an appearance of a uniform, lively, smooth and even surface,with no apparent imperfections. Therefore, there is a need for cosmeticsthat assist in creating a flawless, long lasting, lively coloring toimprove the appearance of the biological surfaces.

Presently, make-up compositions that are applied to biological surfacesto impart a certain color such as foundations, face powders, eyeshadows,lipsticks, concealers, blushers, mascaras, eyeliners, lip pencils, eyepencils, or nail varnishes have difficulty achieving a perfect, flawlesslively color because cosmetic ingredients such as coloring agents, whichprovide the desired color and coverage, generally have many limitations.

The coloring agents employed in such make-up compositions can be lakes,inorganic or organic pigments and/or pearlescent pigments, andalternatively dyes. Inorganic pigments, and in particular inorganicoxides, have the advantage of being relatively stable, but have thedrawback of imparting rather dull, pale colors to the material beingcolored. Organic lakes have the advantage of imparting lively colors tothe compositions, but are relatively unstable with respect to light,temperature or pH. Some of these coloring agents also have the drawbackof leaving unsightly marks on the skin or the nails after application.Pearlescent pigments allow varied, but not intense, colors to beobtained with iridescent effects. Moreover, certain coloring agents havethe drawback of generating free radicals in make-up formulations, whichmodify the color of the applied make-up and the stability of thecompositions. Free radicals, when present on the skin promote ageing ofthe skin such as the appearance of wrinkles, fine lines and yellowing ofthe skin.

Therefore, there remains a need for cosmetic formulations andpreparations that provide the increased color chroma of organic lakeswhile having the stability of inorganic pigments.

The compound eyes of insects are composed of ommatidia. The ommatidiahave smooth surfaces, but some, such as those of moths and butterflies,are covered with tiny, slightly tapered protuberances. These structuresare approximately 200 nanometers in both height and diameter at theirbase, and are arrayed across the surface of the ommatidia in a regularhexagonal pattern. These structures were first observed in nocturnalmoths by W. H. Miller and colleagues in 1962 (Bernhard C. G. and MillerW. H. “A corneal nipple pattern in insect compound eyes,” Acta Physiol.Scand. 1962; 56:385-386). Such structures are shown and described inVukusic, et al., Nature 2003, 424:852-856, for example, FIG. 7.

Because the species that possess these structures tend to be active atnight or in the dark, it is important that they absorb as much of theavailable light as possible. The function of such protuberances seems tobe to reduce reflection of light from the surface of the ommatidia andthereby increase light's absorption by the receptor cells underneath.Like much of the exoskeleton of insects, the surface of each ommatidiumis made of chitin, which has a refractive index (1.55) higher than thatof air (1.00).

The protuberances work by providing a gradual transition in refractiveindex from air to ommatidium. Each individual photon that is incident onthe ommatidia first encounters the thinner tops of the protuberances,making the effective refractive index only slightly higher than therefractive index of air. As the protuberance widens closer to thebottom, the refractive index of the surface approaches that of purechitin. Because the size and periodicity of the protuberances aresmaller than those of the optical wavelengths absorbed (<˜500 nm), eachindividual photon encounters this gradual transition, and reflectionfrom the surface is minimized. This is known as the “moth-eye principle”or the “moth-eye effect”.

The moth-eye structure is well suited for many antireflective tasks. Inthe present application, the inventive cosmetic formulations permitincreased light absorption and provide increased color chroma whilebeing relatively stable.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a composition thatdelivers in an acceptable carrier comprising a film former and/or wax,an effective amount of a nanoparticle material and one or more pigmentssufficient to alter the appearance of a biological surface, where thecomposition controls light transmission, absorption and scattering. Itis a further object to provide cosmetic formulations that provide highcolor chroma. When the inventive formulations are black, it is a furtherobject permit increased light transmission and absorption and reducedlight reflection.

It is another object of the present invention to provide a method ofmaking a composition of nanoparticle material and pigment in acceptablevehicle or carrier.

A further object of the invention is to provide a composition comprisingan effective amount of nanoparticles to produce the optical effectsobserved in the moth eye along with one or more pigments in a carrierwhich further produce unique optical effects on skin. In yet anotherobject, a method of improving the aesthetic or natural appearance of abiological surface by applying to the biological surface a compositioncomprising an effective amount of nanoparticles to produce opticaleffects observed in the moth eye and one or more pigments in a carrierin an amount effective to improve the aesthetic or natural appearance ofthe biological surface. The composition is applied such that theappearance of dermatological signs of damaged or chronologically-aged,hormonally-aged, or photo-aged skin, such as fine lines, wrinkles, andsagging skin, surface imperfections, and discoloration is diminished.

It is another object of the present invention to provide a method ofbeautifying and decorating a biological surface by applying to thebiological surface a composition comprising a carrier having a filmformer and/or wax with an effective amount of nanoparticles and one ormore pigments to produce the optical effects observed in the moth eye.The composition is applied to a biological surface to add color, hidesurface flaws, act as a photoprotectant, and make the surface appearsmoother.

These and other objects and advantages of the present invention, andequivalents thereof, are achieved by compositions having an effectiveamount of nanoparticles along with pigments and combinations thereof,and methods of using such compositions for topical application in orderto improve the aesthetic appearance of a biological surface.

BRIEF DESCRIPTION OF THE DRAWING

FIG. 1 shows a schematic representation of the anti-reflective“moth-eye” surface with the size of the moth-eye structure between 180nm and 240 nm. This sub-visible light wavelength surface relief profileis a low reflectance interface for light. As a result, the moth's eyeappears black and may absorb light from any direction.

FIG. 2 shows the reflectance (total reflection (SCI) and scatteringreflection (SCE)) of four systems: (1) 6.94% carbon black plus 2.78%hydrophobic silica; (2) 6.94% carbon black plus 2.78% hydrophobic fumedsilica; (3) 6.94% carbon black plus 2.78% fumed silica and (4) 7.14%carbon black. The full composition of each system is disclosed in Table2. The figure shows that the addition of silica of any kind reducestotal reflection (SCI—specular component included).

FIG. 3 shows absorbance of the four (4) systems used in FIG. 2. Thefigure shows that the addition of silica of any kind increasesabsorption. The reflection and absorption values for each systemdisclosed in Table 2 are shown in Table 3.

FIG. 4 shows the reflectance (total reflection (SCI) and scatteringreflection (SCE)) of five systems: (5) 6.94% carbon black plus 5.00%fumed silica; (6) 6.94% carbon black plus 7.00% fumed silica; (9) 9.00%carbon black plus 2.78% fumed silica; (11) 9.00% carbon black plus 5.00%fumed silica; and (4) 7.14% carbon black. (The full composition of eachsystem is disclosed in Table 2). The figure shows that the addition offumed silica to carbon black causes a decrease in total reflection.

FIG. 5 shows absorbance of the five systems used in FIG. 4. The figureshows that the addition of fumed silica to carbon black increasesabsorption.

FIG. 6 a shows the absorbance and FIG. 6 b shows the luminescence (L*)data for three (3) systems: 4.00% carbon black control with nonanoparticles, 4.00% carbon black with 4% silica shell nanoparticles,and 4.00% carbon black with 4.00% fumed silica nanoparticles. Thefigures shows that the addition of either 4.00% fumed silicananoparticles or 4.00% silica shell nanoparticles results in increasedabsorbance and reduced luminescence resulting in enhanced contrast(darker) in comparison to the carbon black control (no nanoparticles).The full composition of each system is disclosed in Table 5.

FIG. 7 a shows the total transmission and FIG. 7 b shows the totalreflectance and scattered reflectance data for three (3) systems: 4.00%carbon black control with no nanoparticles, 4.00% carbon black with4.00% silica shell nanoparticles, and 4.00% carbon black with 4.00%fumed silica nanoparticles. The figures show that addition of 4.00%fumed silica nanoparticles results in increased transmission, reducedtotal reflectance and reduced scattered reflectance. The fullcomposition of each system is disclosed in Table 5. The reflection andabsorption values for each system disclosed in Table 5 are shown inTable 6.

DETAILED DESCRIPTION OF THE INVENTION

In accordance with the foregoing objectives and others detailed herein,the invention provides compositions comprising an effective amount ofnanoparticles in combination with a pigment in an acceptable vehiclehaving a film former and/or wax to create optical effects observed inthe moth eye which improve the aesthetic appearance of biologicalsurfaces. The compositions, for example, improve the appearance ofbiological surfaces damaged by the chronological aging process, theenvironment, or natural imperfections. The compositions also serve tobeautify and decorate the biological surfaces. When applied to asurface, for example, a biological surface, the compositions enhance theappearance of the surface by enhancing absorbance, enhancingtransmittance and reducing reflective properties. Enhancing theaesthetic appearance of the biological surfaces may be achieved bytopical application of the inventive compositions to the biologicalsurfaces on a daily basis or when a natural appearance or added color isdesired. Biological surfaces include, but are not limited to, keratinoustissues, skin, hair, lips, eyelashes, eyebrows and nails.

The compositions of the invention alter the manner in which lightreaches a biological surface so as to provide hiding, opacity, andcoverage. The inventive compositions comprise transparent or translucentnanoparticles along with a cosmetic pigment. The nanoparticles incombination with pigment present in a cosmetic composition are suitablefor application to biological surfaces.

The term “nanoparticle” as used herein refers to a nanometer-sizedparticle, having a diameter of between about 1 nanometer and about 999nanometers; the term “nanoparticles” as used herein refers tonanometer-sized particles, nanoclusters, clusters, particles, smallparticles, and nanostructured materials.

An effective amount of nanoparticle material in an acceptable carrierdepends on factors including the weight ratio of nanoparticles pluspigment to film former and/or wax in the carrier, the surface area ofeach nanoparticle, the physical properties of the nanoparticles and theweight ratio of nanoparticles to the pigment. The pigment, carrier andnanoparticle material may each have a different refractive index so asto control light diffusion properties. The refractive index of thepigment is greater than the nanoparticle material to obtain optimallateral light diffusion. The size of each nanoparticle is preferablyless than the wavelength of visible light to enhance light absorptionand reduce reflectance.

Pigments suitable in this invention range in particle size from about100 nanometers to about 10 microns. More preferably, pigment particlesizes range from about 100 nanometers to about 2 microns. Preferredinorganic pigments for use in this invention are those typically used inthe personal care or cosmetic industry to provide hiding, coverageand/or color. In one embodiment of the invention, the pigment materialis about 0.5 microns; in another embodiment of the invention, pigmentmaterial is about 1.0 microns. Reference to the size of a pigment ornanoparticle means the length of the largest straight dimension of thepigment or nanoparticle. By way of example, the size of a sphericalpigment is its diameter, and the size of a spherical nanoparticle is itsdiameter.

The refractive index of the pigments can be from about 1.38 to about3.52; more preferably about 1.40 to about 3.50; more preferably about1.42 to about 3.40; more preferably about 1.60 to about 3.40. Pigmentshaving refractive indices of about 1.38 to about 3.52 include, but arenot limited to, titanium dioxide (rutile or anatase), zinc oxide andiron oxide. The refractive indices of various materials may be evaluatedusing a refractometer. Details with respect to the principles ofrefraction can be found in Optics by Eugene Hecht (Fourth Edition),2002. Details with respect to refractive indices of materials can befound in the CRC Handbook of Chemistry and Physics, 86th Edition,2005-2006, which is herein incorporated by reference in its entirety.

In one embodiment, the composition is comprised of a combination ofpigments of different refractive indices. In another embodiment of theinvention, the composition is comprised of a single pigment.

Suitable inorganic pigments include, but are not limited to, titaniumdioxide, zirconium oxide and cerium oxide, as well as zinc oxide, ironoxide, chromium oxide and ferric blue. Suitable organic pigmentsinclude, but are not limited to, barium, strontium, calcium, andaluminum lakes and carbon black. Any pigment material of the inventivecomposition producing the desired effects may be used, non-limitingexamples of which include a metal oxide, for example, titanium dioxide,iron oxide, and aluminum oxide. For typical pigments used in cosmeticindustry, refer to the Cosmetic Ingredient Dictionary (INCI) andHandbook, 10th Edition (2004), published by the Cosmetic, Toiletry, andFragrance Association (CTFA).

In one embodiment, the composition comprises titanium dioxide. Inanother embodiment, the composition comprises iron oxide. In anotherembodiment, the composition comprises carbon black.

Organic and inorganic pigments suitable for use in this invention may besubstantially solid or porous. In one embodiment, the outer surface ofthe pigment is substantially solid and of uniform contour.

Nanoparticles suitable to create the desired optical effects observed inthe moth eye of this invention range in size from about 1 nm to about900 nm; more preferably from about 7 nm to about 700 nm; more preferablyfrom about 10 nm to about 500 nm. Mean particle sizes of nanoparticlesof this invention range in size from about 10 nm to about 700 nm; morepreferably from about 20 nm to about 500 nm; more preferably from about30 nm to about 500 nm. In various embodiments of the invention, the meanparticle size of the nanoparticles may be about 10 nm, about 20 nm,about 50 nm, about 75 nm, about 100 nm, about 125 nm, about 150 nm,about 175 nm, about 200 nm, about 225 nm, about 250 nm, about 275 nm,about 300 nm, about 325 nm, about 350 nm, about 375 nm, about 400 nm,about 425 nm, about 450 nm, about 475 nm, or about 500 nm. Preferably,the nanoparticles have a diameter below the wavelength of light they areinteracting with, thereby producing the desired effects.

In one embodiment of the invention, the nanoparticles are smaller thanthe size of the pigment. In another embodiment of the invention, thenanoparticles are about the same size as the pigment. In yet anotherembodiment of the invention, the nanoparticles are larger than the sizeof the pigment.

Nanoparticles suitable for this invention include, but are not limitedto, nanoparticles made of fumed silica, metal oxides such as aluminumoxide, fumed alumina, zinc oxide, titanium dioxide or zirconium oxide,or polymeric nanoparticles such as poly(methyl methacrylate) (PMMA),nylon, polyethylene (PE), polystyrene (PS), polytetrafluoroethylene, orcellulosics. The refractive index of the nanoparticles can be from about1.30 to about 3.50. In one embodiment of the invention, the nanoparticleis fumed silica having a refractive index of about 1.46. In oneembodiment, the composition is comprised of a combination ofnanoparticles of different refractive indices.

The nanoparticles in the composition are capable of enhancing theabsorption and/or altering the scattering behavior of visible light. Thedifference between the refractive indices of the cosmetic pigment andnanoparticle material may range from about 0.01 to about 2.0. In oneembodiment of the invention, the difference between the refractiveindices of the cosmetic pigment and nanoparticle material is about 2.0.In another embodiment of the invention, the difference between therefractive indices of the cosmetic pigment and nanoparticle material isabout 1.0. In another embodiment of the invention, the differencebetween the refractive indices of the cosmetic pigment and nanoparticlematerial is about 0.7. In another embodiment of the invention, thedifference between the refractive indices of the cosmetic pigment andnanoparticle material is about 0.5.

Compositions comprising a pigment having a high refractive index alongwith nanoparticles having a low refractive index permit a change in thedirection of light at the surface interface to occur thus enhancinglight absorption and diffusion, and reducing light reflection andscattering which results in high coverage along with reduced glossiness,enhanced natural or added color contrast and a blurring effect. In oneembodiment of the invention, the refractive index of the cosmeticpigment is about 2.02; in another embodiment of the invention, therefractive index of the pigment is about 2.19.

Weight ratio of the nanoparticles to the pigment particles in theinventive compositions may range from about 10.0:1.0 to about 1.0:10.0.Weight ratios determine the relative percentage of nanoparticles to thepigment particles, thereby affecting the refractive index of thecomposition. In one embodiment of the invention, the composition has aweight ratio of nanoparticles to pigment particles of about 4.0:1.0; inanother embodiment of the invention, the composition has a weight rationof nanoparticles to pigment particles of about 1.0:4.0; in anotherembodiment of the invention, the composition has a weight ration ofnanoparticles to pigment particles of about 1.0:1.0; in anotherembodiment of the invention, the composition has a weight ratio ofnanoparticles to pigment particles of about 1.0:1.4; in yet anotherembodiment of the invention, the composition has a weight ratio ofnanoparticles to pigment particles of about 1.0:1.8; in anotherembodiment of the invention, the composition has a weight ratio ofnanoparticles to pigment particles of about 1.0:3.0. In a preferredembodiment of the invention the composition has a weight ratio ofnanoparticles to pigment particles of about 1.0:1.4.

The weight ratio of nanoparticles plus pigment particles to film formerand/or wax present in the carrier may range from about 100.0:1.0 to1.0:5.0, more preferably from about 100.0:1.0 to about 1.0:1.75, morepreferably from about 100.0:1.0 to about 1.05:1.0, more preferably fromabout 20.0:1.0 to about 1.05:1.0, more preferably from about 10.0:1.0 toabout 1.05:1.0, more preferably from about 2.0:1.0 to about 1.05:1.0.The weight ratio of nanoparticles plus pigment particles to film formerand/or wax present in the carrier determines the relative percentage ofnanoparticles within the composition that are responsible for creatingthe optical effects observed in the moth eye, that is, increasing thelight absorbance.

In the L* a* b* color space (also known as CIELAB), L* indicateslightness and a* and b* are the color directions. L* is measured from 0(black) to 100 (white). The values of a* and b* are plotted in the xycoordinate plane such that +a is red, −a is green, +b is yellow, and −bis blue. The origin (center) of the a* b* plane is achromatic, and anincrease in (+/−) a* or (+/−) b* results in an increase of the colorchroma. When the inventive formulations have colored pigments, theformulations have increased color chroma, that is, increased (+/−) a* or(+/−) b* values. When the inventive formulations are black, theformulations have increased light absorption and decreased lightreflection, that is, a decreased L* value (i.e., a more intense black).Table 1 shows examples of mascara formulations and their respective L*values. The mascara formula with the hydrophobic amorphous fumed silicashows the lowest L*.

TABLE 1 Examples of mascara formulations demonstrating their respectiveL* values 1 2 3 Kobo Black iron oxide pigment 4.00 4.00 4.00 Aeroxide LE3 (deGussa) 0 4.00 0 Cadre Hydrophobic Amorphous Fumed 4.00 0 0 Silica #79684 KP-550 (Shin Etsu) 5.60 5.60 5.60 Versagel MD 1600 (Panerco) 56.0056.00 56.00 Isododecane 30.40 30.40 30.40 (TOTAL) 100 100 100 L* Value15.40 19.00 25.00

In one embodiment of the invention, the weight ratio of nanoparticlesplus pigment particles to film former and/or wax present in the carrieris about 1.0:1.0; in another embodiment of the invention, the weightratio of nanoparticles plus pigment particles to film former and/or waxpresent in the carrier is about 1.4:1.0. In one embodiment of theinvention, the weight ratio of nanoparticles plus pigment particles tofilm former and/or wax present in the carrier is about 1.7:1.0; inanother embodiment of the invention, the weight ratio of nanoparticlesplus pigment particles to film former and/or wax present in the carrieris about 2.0:1.0

Suitable film formers for use in the inventive compositions include, butare not limited to, sulfopolyester resins, polyvinylacetate, polyvinylalcohol polymers, acrylic resins, silicone acrylate polymers (such asthose available from Shin Etsu), polyvinylpyrrolidones, high molecularweight silicones, organosiloxanes, polyurethanes, hydrophobic acrylatecopolymers, as well as others known in the art (for example those listedin WO 03/105790, incorporated herein). The film former is preferablypresent from about 0.01 weight % to about 20 weight % of the totalweight of the composition. In one embodiment, the film former is apolymer. In one embodiment, the film former is silicone acrylatecopolymer.

In one embodiment of the invention, the composition includes one or morewaxes, gums, or mixtures thereof. Suitable waxes includehydrocarbon-based waxes, fluoro waxes and/or silicone waxes and can beof plant, mineral, animal and/or synthetic origin. In particular, thewaxes have a melting point of greater than 25° C., preferably greaterthan 45° C. The compositions of the present invention may contain fromabout 0.1 weight % to about 20 weight % waxes, based upon the totalweight of the composition. The gums are generally high molecular weightpolydimethylsiloxanes (PDMSs), cellulose gums or polysaccharides, andthe semi-solid materials are generally hydrocarbon-based compounds, suchas, but not limited to, lanolins and derivatives thereof, oralternatively PDMSs. The compositions of the present invention maycontain from about 0.1 weight % to about 20 weight % gums, based uponthe total weight of the composition, typically from about 0.5 weight %to about 10 weight %.

The surface area of the nanoparticles of the inventive compositions mayrange from about 20 m²/g to about 700 m²/g; more preferably about 50m²/g to about 500 m²/g; more preferably about 70 m²/g to about 400 m²/g.Surface area of the nanoparticles governs the multiple scattering oflight in the composition.

The compositions of the present invention can be prepared by combining aspecific amount of pigment, nanoparticles, and a carrier with alreadypremixed solvents, one or more film-formers and/or waxes and otherdesired ingredients. The components are to be mixed with very high shearblade mixers for a sufficient period of time to make a homogeneousmixture. It will be recognized that the time and the sequence of addingcompounds may vary depending on the components of the desiredcomposition.

The compositions of the present invention provide increased color chromaof the pigment used, regardless of the type of pigment employed.Accordingly, the inventive compositions can provide color chroma fromorganic pigments that is similar to color chroma of organic lakes. Suchcompositions would then have the benefit of high color chroma usuallyassociated with organic pigments but with the stability associated withinorganic pigments.

In situations where the inventive compositions lack a pigment it isbelieved that the compositions will increase light transmission andprovide increased color chroma of a biological surface to which thecompositions are applied. Such inventive compositions are useful forenhancing the natural color of a biological surface. In situations wherethe inventive composition lacks a pigment, the weight ratio ofnanoparticles to film former and/or wax present in the carrier may rangefrom about 100.0:1.0 to 1.0:5.0, more preferably from about 20.0:1.0 toabout 1.05:1.0, more preferably from about 10.0:1.0 to about 1.05:1.0,more preferably from about 2.0:1.0 to about 1.05:1.0.

In the moth's eye, the light enters the crevices between conicalprotrusions that are less than 500 nm in diameter (FIG. 1). Theinventive compositions may contain nanoparticles having a low refractiveindex; the inventive compositions have nanoparticles that are preferablyof sub-visible light wavelength size to create the optical effectsobserved in the moth eye.

Without wishing to be bound by any particular theory or mechanism, it isbelieved that when a composition of the invention is applied as a layerto a biological surface, the nanoparticles aggregate on the layer'souter surface (that is, the surface opposite to the surface adjacent tothe biological surface). If such aggregation occurs, then the layer'souter surface would have a morphology similar to that of a moth's eye.The nanoparticle aggregation on the layer's outer surface would bedependent on the weight ratio of nanoparticles plus pigment to filmformer in the carrier. At specific weight ratios disclosed herein, thenanoparticles of the inventive compositions are exposed to incidentlight. It is believed that when incident light strikes thenanoparticles, light is absorbed and scattered which decreases lightreflectance.

Design and choice of nanoparticles may increase the angle of incidenceto greater than the critical angle for total internal reflection, thusenhancing the light diffusion along the interface of nanoparticles andpigment. By using nanoparticles having a low reflective index, one canobtain high coverage along with enhanced color. A composition comprisingnanoparticles having a low refractive index along with a pigment havinga high index of refraction enables the composition to produce a morenatural appearance when applied to skin by enhancing transmittance.

The advantages of the inventive composition include, but are not limitedto, the simplicity of providing enhanced color and while employingcosmetically acceptable pigments and carriers.

If the nanoparticles in the inventive compositions are small, forexample, about 100 nanometers or less, then films and coatings may beproduced that, in addition to creating optical effects observed in themoth eye, may also provide ultraviolet (UV) protection. Anotheradvantage of the nanoparticles is that they may absorb oil, sebum, andmoisture. These properties provide additional benefits in cosmetic anddermatological formulations or compositions, and enhance the aestheticand natural appearance of biological surfaces.

Compositions of the present invention have optical properties whichenhance the aesthetic and natural appearance of a biological surface byenhancing the color of the pigments or dyes. When applied to abiological surface, the inventive compositions result in opticalblurring and increased light transmittance, light scattering andreduced, thereby reducing the appearance of dermatological signs ofchronological-aging, photo-aging, hormonal-aging, and/or actinic-aging;reducing the appearance of lines and/or wrinkles; reducing thenoticeability of facial lines and wrinkles, facial wrinkles on thecheeks, forehead, perpendicular wrinkles between the eyes, horizontalwrinkles above the eyes, and around the mouth, marionette lines, andparticularly deep wrinkles or creases; reducing the appearance and/ordepth of lines and/or wrinkles; improving the appearance of suborbitallines and/or periorbital lines; reducing the appearance of crow's feet;improving the appearance of rejuvenating and/or revitalizing skin,decreasing the appearance of aging skin; reducing the appearance of skinfragility; reducing the appearance of a loss of glycosaminoglycansand/or collagen; reducing the appearance of estrogen imbalance; reducingthe appearance of skin atrophy; reducing the appearance ofhyperpigmentation; reducing the appearance of skin discoloration;improving the appearance of skin tone, radiance, clarity and/ortautness; reducing the appearance of sagging skin; improving theappearance of skin firmness, plumpness, suppleness and/or softness;improving the appearance of procollagen and/or collagen production;improving the appearance of skin texture and/or retexturization;improving the appearance of skin barrier repair and/or function;improving the appearance of skin contours; improving the appearance ofdecreased skin luster and/or brightness; improving the appearance ofdermatological signs of fatigue and/or stress; improving the appearanceof environmental stress; improving the appearance of cellular aging;improving the appearance of skin dehydration; improving the appearanceof elastic and/or resilient skin; improving the appearance ofmicrocirculation; decreasing the appearance of cellulite formation; orany combinations thereof.

Another embodiment of the invention relates to a method of improving theaesthetic or natural appearance of a biological surface comprisingapplying to the biological surface, including but not limited to,keratinous tissue, skin, hair and nails, the inventive compositionhaving the characteristics and properties described herein, in an amounteffective to improve the aesthetic or natural appearance of thebiological surface.

The biological surface may be any surface to which cosmetics, personalcare products, dermatological, and pharmaceutical compositions aretypically applied, including but not limited to skin, lips, hair, nails,and the like. The composition that is applied to skin improves orenhances the aesthetic appearance of skin by camouflaging the naturalaging process, discoloration, chronic and cumulative damage tobiological surfaces, and imperfections on the surface. The compositionthat is applied to keratinous surface or a mucous membrane improves orenhances the aesthetic appearance of the surface by enhancing thenatural color and color added in the form of the pigment.

Embodiments of the invention relate to the discovery that nanoparticlesin a composition that produces optical effects observed in the moth eyecan camouflage biological surface flaws and add color with increasedchroma to the biological surface. Thus, the optical properties of theinventive compositions enable one to camouflage imperfections ofbiological surfaces and add colors and shades with increased chroma,thereby improving the aesthetic and natural appearance of biologicalsurfaces. The optical properties of the inventive compositions alsoallow one to beautify and decorate a biological surface.

One embodiment of the invention relates to methods of applying theclaimed composition to an affected area of the skin. The composition ispreferably applied topically as desired by the user any number of timesduring the day, and remains on the affected area of the skin, where theaffected area of the skin includes, but is not limited to, the face,neck, legs and thighs, scalp, and overall body. Topical compositionspreferably have the aforementioned nanoparticles in combination withpigments which improves the cosmetic and/or aesthetic appearance ofskin, particularly of aging and/or inflamed skin.

The inventive compositions are useful in improving the natural andaesthetic appearance of biological surfaces including skin, lips, hair,and nails, when applied, preferably topically as many times as desiredby the user to the biological surface. The compositions of the inventionmay also include, in addition to a carrier or vehicle, non-limitingexamples of active ingredients useful in reducing, diminishing, orcamouflaging medical and/or cosmetic conditions associated with aging,inflammation, and degeneration of the biological surface. Suchconditions, as used herein, commonly include, but are not limited to,dermatological aging (chronological aging, hormonal aging and/or actinicaging), dermatitis, skin and hair fragility, hirsutism, rosacea, skinblemishes, sensitive skin, hyperpigmentation or hypopigmentation,thinning skin, roughness, keratosis, skin atrophy, wrinkles, lines,hyperplasia, fibrosis, and any combinations thereof. The activecomponents of the present invention may also be useful in enhancing thegeneral health, vitality, condition, and aesthetic appearance of theskin.

In accordance with the invention, compositions having the desiredproperties may be useful in topically applied formulations,anti-oxidants, anti-inflammatories, sunscreens, cosmetics, includingmakeup, and formulations for reducing dermatological signs of aging,including wrinkles, fine lines, and sagging skin, and the like. Also inaccordance with this invention, compositions may be formulated in avariety of product forms. The compositions may be prepared in targeteddelivery systems, e.g. creams, lotions, moisturizers, gels, toners,serums, sprays, foams, powders, and the like, particularly for topicalapplication and administration.

The inventive compositions are preferably for topical administration orfor targeted delivery without inducing significant irritation. Theinventive compositions are suitable for all skin types, such assensitive, normal, dry, or oily, preferably sensitive to dry skin, aswell as mature skin. In particular embodiments, the compositions may besuitable for dry skin. The compositions are applied to the skin for aperiod of time sufficient to enhance the natural and aestheticappearance of skin. The compositions may be applied topically once,twice, or more daily to biological surfaces, including but not limitedto skin, lips, and hair.

The topical compositions may be formulated into liposomes which maycomprise other additives or substances, and/or which may be modified tomore specifically reach or remain at a site following administration.The compositions of embodiments of the present invention yieldimprovements to the aesthetic appearance of skin by camouflaging orimproving upon at least one of the previously described conditions, orcombinations thereof.

The inventive compositions may be topically applied as described hereinaccording to the routine technique for administering such compositions.The topical cosmetic, dermatological, or pharmaceutical compositionpreferably is applied once or multiple times daily. The cosmeticcomposition is preferably applied to the face and neck, but may beapplied to any area of skin in need of aesthetic improvement, where thecosmetic composition remains on the affected area of skin, andpreferably not removed or rinsed off the skin. Routine and commonlypracticed techniques encompass the application of creams, lotions, gels,sera, ointments, makeup, sunscreen compositions, or the like, to theskin. Preferably the cosmetic composition is a topical leave onformulation, where spraying as a form of application is also envisioned.

The inventive compositions are suitable for contact with livingmammalian tissue, including human tissue, or synthetic equivalentsthereof, with virtually no adverse physiological effect to the user.Compositions embraced by this invention can be provided in anycosmetically and/or dermatologically suitable form, preferably as alotion or cream, but also in an anhydrous or aqueous base, as well as ina sprayable liquid form. Other suitable cosmetic product forms for thecompositions of this invention include but are not limited to, forexample, an emulsion, a cream, a balm, a gloss, a lotion, a foam, amask, a serum, a toner, an ointment, a mousse, a patch, a pomade, asolution, a spray, a wax-based stick, or a towelette. In addition, thecompositions contemplated by this invention can include one or morecompatible cosmetically acceptable adjuvants commonly used and known bythe skilled practitioner, such as fragrances, emollients, humectants,preservatives, vitamins, chelators, thickeners, perilla oil or perillaseed oil (WO 01/66067 to a “Method of Treating a Skin Condition,”incorporated herewith) and the like, as well as other botanicals such asaloe, chamomile, and the like, and as further described below.

The nanoparticles in combination with pigment of the present inventionmay be contained in a cosmetically, dematologically, physiologically,and pharmaceutically acceptable vehicle, medium, diluent or carrier, foruse in reducing, ameliorating, or preventing the dermatological signsassociated with aging and inflammation of biological surfaces. In anembodiment embracing topical applications, the compositions of thisinvention comprise a medium (vehicle, diluent or carrier) that iscompatible with mammalian biological surfaces, including skin, lips,hair and nails. The compositions can be formulated as an aqueous phase,an oil phase, alcohol, or aqueous/alcohol-based solutions, ointments,creams, lotions, gels, a wax-in-water emulsion, or water-in-oil,oil-in-water, of water-oil-water triple emulsions having the appearanceof a cream or gel, microemulsions, or aerosols.

The aqueous phase is a mixture of one or more water soluble or waterdispersible ingredient, which can be liquid, semi-solid or solid at roomtemperature (25° C.). The vehicle comprises or can be in the form of asuspension, dispersion or solution in water or an aqueous-alcoholicvehicle, which may contain a thickener or gellant. A person skilled inthe art can select the appropriate cosmetic form, the ingredientscontained therein, as well as the method for preparing it, on the basisof the knowledge that the skilled artisan possesses.

In one embodiment, the composition may include an aqueous phase whichmay contain water or a mixture of water and at least one hydrophilicorganic solvent in particular an alcohol, especially a linear orbranched lower monoalcohol containing from 2 to 5 carbon atoms, e.g.,ethanol or propanol; a polyol, e.g., propylene glycol, sorbitol,glycerol, diglycerol, panthenol, or polyethylene glycol, and mixturesthereof. This aqueous phase may represent from about 0.5 weight % toabout 99.99 weight %, based upon the total weight of the composition.

In another embodiment when the composition of the invention is in theform of an emulsion, the composition may also optionally comprise asurfactant, preferably in an amount of from about 0.1 weight % to about30 weight %, and in particular, from about 1 weight % to about 20 weight%, based upon the total weight of the composition.

In a further embodiment of the invention, the composition may alsocomprise a thickening polymer such as an amphiphilic polyurethane, apolyacrylic homopolymer or copolymer, a polyester, or ahydrocarbon-based resin. Other non-limiting polymers include,homopolymers or copolymers of: vinyl esters of an aliphatic aid having 1to 18 carbon atoms, such as vinyl acetate; acrylic acid esters andmethacrylic acid esters of an alcohol having 1 to 18 carbon atoms, suchas methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexylacrylate, methyl methacrylate, ethyl methacrylate and butylmethacrylate; and mono and di-ethylenically unsaturated hydrocarbons,including ethylene iso-butylene, styrene and aliphatic dunes, includingbutadiene, isoprene and chloroprene.

One embodiment of the invention further relates to a composition of theinvention which may also comprise an oil phase containing oil soluble oroil dispersible ingredients that are liquid at room temperature (25° C.)and/or oily or waxy substances that are solid at room temperature, suchas waxes, semi-solids, gums, and mixtures thereof. This oily phase mayalso contain organic solvents.

Suitable oily materials that are liquid at room temperature, oftenreferred to as oils, include hydrocarbon-based oils of animal originsuch as perhydrosqualene; hydrocarbon-based plant oils such as liquidtriglycerides of fatty acids of 4 to 10 carbon atoms, for instance,heptanoic or octanoic acid triglycerides, or oils such as sunflower oil,corn oil, soybean oil, grapeseed oil, castor oil, avocado oil,caprylic/capric acid triglycerides, jojoba oil; linear or branchedhydrocarbons of mineral or synthetic origin such as liquid paraffins andderivatives thereof, petroleum jelly; synthetic esters and ethers, inparticular esters of fatty alcohols, namely; for example, isopropylmyristate, 2-ethylhexyl palmitate, 2-octyldodecyl stearate, isostearylisostearate; hydroxylated esters such as isostearyl lactate, octylhydroxystearate, octyldodecyl hydroxystearate, heptanoates, octanoatesand decanoates of fatty alcohols; polyol esters such as propylene glycoldioctanoate, neopentyl glycol diheptanoate, diethylene glycoldiisononanoate, and pentaerythritol esters; fatty alcohols containingfrom 12 to 26 carbon atoms such as octyldodecanol, 2-butyloctanol,2-hexyldecanol, 2-undecylpentadecanol, oleyl alcohol; partiallyhydrocarbon-based fluoro oils and/or fluorosilicone oils; silicone oilssuch as volatile or non-volatile, linear or cyclic polydimethylsiloxanes(PDMS) that are liquid or semisolid at room temperature such ascyclomethicones and dimethicones, optionally comprising a phenyl group,for instance phenyl trimethicones, siloxanes, and mixtures thereof.These oils are usually present in an amount of about 0 weight % to about90 weight %, preferably from about 1 weight % to about 80 weight % byweight of the oil phase.

The oil phase of the composition of the invention may also comprise oneor more cosmetically acceptable organic solvents. These solvents arepresent in an amount of about 0.1 weight % to about 80 weight %,preferably about 1 weight % to about 50 weight %, based on the totalweight of the composition, and may be selected from the group consistingof lipophilic organic solvents, amphiphilic organic solvents andmixtures thereof. Suitable solvents which may be used in the compositionof the invention include acetic acid esters such as methyl, ethyl,butyl, amyl or 2-methoxyethyl acetate; isopropyl acetate; hydrocarbonssuch as toluene, xylene, p-xylene, hexane or heptane; ethers containingat least 3 carbon atoms, and mixtures thereof.

The composition of the invention may further comprise any ingredientconventionally used in the cosmetics field. These ingredients includepreserving agents, aqueous phase thickeners (polysaccharide biopolymers,synthetic polymers) and fatty-phase thickeners, fragrances, hydrophilicand lipophilic active agents, and mixtures thereof. The amounts of thesevarious ingredients are those conventionally used in the cosmetics fieldto achieve their intended purpose, and range typically from about 0.1weight % to about 20 weight %, based upon the total weight of thecomposition. The nature of these ingredients and their amounts must becompatible with the production of the compositions of the invention.

The composition of the invention may also comprise an additionalparticulate phase, typically present in an amount of about 0.1 weight %to about 30 weight %, based upon the total weight of the composition,preferably from about 0.5 weight % to about 20 weight %, and which cancomprise pearlescent agents and/or fillers used in cosmeticcompositions. Suitable pearlescent agents include mica coated withtitanium dioxide or with iron oxide.

Fillers are normally present in an amount of about 0.1 weight % to about30 weight %, based on the total weight of the composition, preferablyabout 0.5 weight % to about 15 weight %. Suitable fillers include talc,silica, zinc stearate, mica, kaolin, nylon (in particular orgasol)powder, polyethylene powder, Teflon®, starch, boron nitride, copolymermicrospheres such as Expancel® (Nobel Industrie; Sweden), Polytrap® (DowCorning, Inc.; Midland, Mich.), and silicone resin microbeads(Tospearl®; GE Toshiba Silicones; Japan).

More particularly, the compositions for topical application can be inthe form of a protective care composition for the skin, preferably forthe face, the neck, the hands, the feet, or other areas of the body.Non-limiting examples include day creams or lotions, night creams orlotions, moisturizer, salves, sunscreen creams, lotions, or oils,ointments, gels, body milks, makeup (a foundation, a bronzer),artificial tanning compositions, depilatories, patches, emulsifiers, ora solid which is poured or cast as a stick or a dish, for example. Theinventive compositions are ideal for use in a foundation product becauseit may achieve high camouflage and blurring effects to result in theperception of a natural appearance.

In another embodiment, the topical compositions of the present inventionmay also include one or more of the following: a skin penetrationenhancer, an emollient, a skin plumper, an optical diffuser, asunscreen, an exfoliation promoter, and an antioxidant. Details withrespect to these and other suitable cosmetic ingredients can be found inthe International Cosmetic Ingredient Dictionary (INCI) and Handbook,10th Edition (2004), published by the Cosmetic, Toiletry, and FragranceAssociation (CTFA), at pp. 2177-2299, which is herein incorporated byreference in its entirety.

An emollient provides the functional benefits of enhancing skinsmoothness, reducing the appearance of fine lines and coarse wrinkles,and moisturizing. Non-limiting examples include isopropyl myristate,petrolatum, isopropyl lanolate, silicones (e.g., methicone,dimethicone), oils, mineral oils, fatty acid esters, or any mixturesthereof. The emollient is preferably present from about 0.1 weight % toabout 50 weight % of the total weight of the composition.

A skin plumper serves as a collagen enhancer to the skin. An example ofa suitable, and preferred, skin plumper is palmitoyl oligopeptide. Otherskin plumpers are collagen and/or glycosaminoglycan (GAG) enhancingagents. The skin plumper is preferably present from about 0.1 weight %to about 20 weight % of the total weight of the composition.

In addition to the nanoparticles and pigment, optical diffusers or softfocus materials that change the surface optical properties of skin,resulting in a visual blurring and softening of, for example, lines andwrinkles are contemplated. Examples of optical diffusers that can beused in the present invention include, but are not limited to, boronnitride, mica, nylon, polymethylmethacrylate (PMMA), polyurethanepowder, sericite, silica, silicone powder, talc, Teflon®, titaniumdioxide, zinc oxide, or any mixtures thereof. The optical diffuser ispreferably present from about 0.01 weight % to about 20 weight % of thetotal weight of the composition.

A sunscreen protects the skin from damaging ultraviolet rays. In anillustrative embodiment of the invention, the sunscreen would provideboth UVA and UVB protection, by using either a single sunscreen or acombination of sunscreens. Among the sunscreens that can be employed inthe present compositions are avobenzone, cinnamic acid derivatives (suchas octylmethoxy cinnamate), octyl salicylate, oxybenzone, non-mesoporoustitanium dioxide, zinc oxide, or any mixtures thereof. The sunscreen maybe present from about 1 weight % to about 30 weight % of the totalweight of the composition. The addition of a sunscreen may protect theskin from ultraviolet radiation. As explained above, UV protection mayalso be achieved by utilizing nanoparticles of about 100 nanometers orless.

The inventive compositions having sunscreen bring about additionalimprovements to the aesthetic appearance of skin, including at least oneof the following: minimizes sunburning, minimizes tanning, and reducesredness.

In an embodiment of the invention, compositions may also have one ormore exfoliation promoters. Suitable examples of an exfoliation promoterthat can be used in the present compositions include alpha hydroxy acids(AHA); benzoyl peroxide; beta hydroxy acids; keto acids, such as pyruvicacid, 2-oxopropanoic acid, 2-oxobutanoic acid, and 2-oxopentanoic acid;oxa acids as disclosed in U.S. Pat. Nos. 5,847,003 and 5,834,513 (thedisclosures of which are incorporated herein by reference); salicylicacid; urea; or any mixtures thereof. One preferred exfoliation promotersare 3,6,9-trioxaundecanedioic acid, glycolic acid, lactic acid, or anymixtures thereof (See also, INCI at p. 2205).

When an embodiment of the invention includes an exfoliation promoter,the composition has about 0.1 weight % to 30 weight %, preferably about1 weight % to about 15 weight % and more preferably about 1 weight % toabout 10 weight %, of the exfoliation promoter based on the total weightof the composition.

An antioxidant functions, among other things, to scavenge free radicalsfrom skin to protect the skin from environmental aggressors. Examples ofantioxidants that may be used in the present compositions includecompounds having phenolic hydroxy functions, such as ascorbic acid andits derivatives/esters; beta-carotene; catechins; curcumin; ferulic acidderivatives (e.g. ethyl ferulate, sodium ferulate); gallic acidderivatives (e.g. propyl gallate); lycopene; reductic acid; rosmarinicacid; tannic acid; tetrahydrocurcumin; tocopherol and its derivatives;uric acid; or any mixtures thereof. Other suitable antioxidants arethose that have one or more thiol functions (—SH), in either reduced ornon-reduced form, such as glutathione, lipoic acid, thioglycolic acid,and other sulfhydryl compounds. The antioxidant may be inorganic, suchas bisulfites, metabisulfites, sulfites, or other inorganic salts andacids containing sulfur. Compositions of the present invention may havean antioxidant preferably from about 0.001 weight % to about 10 weight%, and more preferably from about 0.01 weight % to about 5 weight %, ofthe total weight of the composition. (See also, INCI at p. 2184).

In one embodiment of the invention, the composition may also have one ormore of the following cosmetic and pharmaceutical active agents,excipients, ingredients, or adjuvants: anesthetics, antibiotics, e.g.,erythromycins and tetracyclines, salicylic acids, anti-allergenics,antifungals, antiseptics, anti-irritants, anti-inflammatory agents,antimicrobials, analgesics, nitric oxide synthase inhibitors, insectrepellents, self-tanning agents, skin penetration enhancers, skincooling agents, chelating agents, colorants including dyes, lakes andpigments that may be untreated or chemically surface treated to improvewettability or some other property, demulcents, emollients, emulsifiers,fragrances, humectants, lubricants, skin protectants, moisturizers, pHadjusters, preservatives, stabilizers, surfactants, thickeners,plasticizers, viscosity modifiers, vitamins, or any mixtures thereof.The amounts of these various substances are those that areconventionally used in the cosmetic or pharmaceutical fields to achievetheir intended purposes, for example, they may constitute from about0.01% to 20% of the total weight of the composition.

Non-limiting examples of active agents for formulating into thecompositions of the invention include those reagents having an effect onthe treatment of wrinkles and/or fine lines, in addition to the activesas described, such as keratolytic agents, i.e., an active agent havingdesquamating, exfoliant, or scrubbing properties, or an active agentwhich can soften the horny layer of the skin. Other examples ofanti-wrinkle or anti-fine line active agents include hydroxy acids andretinoids. These agents can be formulated, for example, in amounts offrom about 0.01% to 5% by weight relative to the total weight of thecomposition.

Suitable hydroxy acids include, for example, glycolic acid, lactic acid,malic acid, tartaric acid, citric acid, 2-hydroxyalkanoic acid, mandelicacid, salicylic acid and alkyl derivatives thereof, including5-n-octanoylsalicylic acid, 5-n-dodecanoylsalicylic acid,5-n-decanoylsalicylic acid, 5-n-octylsalicylic acid,5-n-heptyloxysalicylic acid, 4-n-heptyloxysalicylic acid and2-hydroxy-3-methylbenzoic acid or alkoxy derivatives thereof, such as2-hydroxy-3-methyoxybenzoic acid.

Emulsifiers are typically present in the compositions of the inventionin an amount of about 0.01 weight % to 30 weight %, by weight andpreferably from about 0.1 weight % to 30 weight % by weight relative tothe total weight of the composition. However, not all compositions willnecessarily include emulsifiers. (See e.g., INCI at p. 2276-2285).

Non-limiting examples of suitable thickening agents include xanthan gum,hydroxypropyl cellulose, hydroxyethyl cellulose, carbomer, gum acacia,Sepigel 305 (available from Seppic Co., France), and clays such asmagnesium aluminum silicate. (See, e.g., INCI at p. 2293-2299).

The topical compositions of the present invention may include, and theirutility can be enhanced by, one or more humectants, such as ureas,pyrrolidone carboxylic acids, amino acids, sodium hyaluronates, certainpolyols and other compounds with hygroscopic properties. (See INCI at p.2244).

The general activity and mildness to skin of the present topicalcompositions can also be enhanced by neutralization to pH about 3.5 toabout 7.0, most preferably from pH about 3.7 to about 5.6. Thisneutralization is preferably accomplished with one or more of ammoniumhydroxide, potassium hydroxide, sodium hydroxide, arginine or otheramino acids, and/or triethanolamine.

Exemplary retinoids include, without limitation, retinoic acid (e.g.,all-trans or 13-cis) and derivatives thereof, retinol (Vitamin A) andesters thereof, such as retinol palmitate, retinol acetate and retinolpropionate, and salts thereof.

The nanoparticles and pigment of the present invention may be containedin a cosmetically or dermatologically acceptable vehicle, medium,diluent or carrier. The inventive compositions may be further formulatedaccording to procedures known in the art to provide cosmeticcompositions such as emulsions, gels, creams, lotions, masks, toners,serums, oils, water-in-oil, oil-in-water, water-oil-water tripleemulsions having the appearance of a cream or gel, microemulsions,ointments, pastes, sticks, cakes, pencils, aerosol, and essences, aswell as other topical cosmetic vehicles. It is also contemplated thattopical compositions of the present invention can be incorporated intodelivery systems such as liposomes and topical patches, tapes, andsprays.

In addition, the compositions may be in the form of vesiculardispersions containing ionic and/or nonionic lipids, as described above.Dosage units suitable for such compositions are formulated according tothe conventional knowledge and techniques used in the art.

EXAMPLE

The following example describes specific aspects of the invention toillustrate the invention and provide a description of the presentmethods for those skilled in the art. The example should not beconstrued as limiting the invention, as the example merely providesspecific methodology useful in the understanding and practice of theinvention and its various aspects.

This example examines the effect of adding nanoparticles to acomposition comprising a color pigment in the concentration enough toeffectively create optical effects observed in the moth eye. A GretagMacBeth Color Eye 7000A Spectrophotometer was used to quantifytransmittance, reflection and absorbance (Absorbance=100−(TotalTransmittance+SCI Reflection)).

Physical blends of compositions comprising nanoparticles were preparedusing a speed mixer with silicone acrylate copolymer (KP 550 from ShinEtsu)—which is 40% polymer in isododecane (IDD). Solutions were cast onclean (optically transparent/colorless) glass plates to give a wet filmthickness of approximately 125 microns and dried overnight to form dryfilms with a resulting dry film thickness of 21-25 microns based onsolid content. Samples were prepared in duplicate. Average luminescence(L*) was collected directly using the same sample area for totalreflection (specular component included—SCI) and scattered reflection(specular component excluded—SCE). Data was collected in two distinctareas for each sample, resulting in four data points per sample. TheQ-test was used to remove erroneous data points. All error bars shownare ±one standard deviation. The summary of prepared samples is shownbelow in Tables 1 and 2. For the samples reported in Tables 1 and 2, thecolor pigment is carbon black (D&C Black #2) and values are reported asweight % of the whole composition.

FIG. 2 shows the reflectance (total reflection (SCI) and scatteringreflection (SCE)) of compositions 1, 2, 3, and 4 (control) which wereprepared as shown in Table 2. The figure shows that the addition ofsilica nanoparticles of any kind reduces total reflection (SCI—specularcomponent included) without changing diffuse reflection (SCE—specularcomponent excluded), within error limits.

TABLE 2 Physical blends of compositions comprising nanoparticles CadreCarbon Hydrophobic Degussa Black, Hydrophobic Amorphous Aeroxide D&CSilica Shells- Fumed LE 3 KP-550, Black SH (Kobo Silica Fumed Film IDD,Total Batch # #2 Products) #79684 Silica former Solvent (parts) 1 6.942.78 0 0 6.94 83.34 100 2 6.94 0 2.78 0 6.94 83.34 100 3 6.94 0 0 2.786.94 83.34 100 4 7.14 0 0 0 7.14 85.72 100 5 6.94 0 0 5.00 6.94 81.12100 6 6.94 0 0 7.00 6.94 79.12 100 7 6.94 0 5.00 0 6.94 81.12 100 8 6.940 7.00 0 6.94 79.12 100 9 9.00 0 0 2.78 6.94 81.28 100 10 11.0 0 0 2.786.94 79.28 100 11 9.00 0 0 5.00 6.94 79.06 100 12 0 0 7.14 0 7.14 85.72100 13 0 0 0 7.14 7.14 85.72 100

FIG. 3 shows the absorbance of compositions 1, 2, 3, and 4 (control)which were prepared as shown in Table 2. The figure shows that theaddition of silica of any kind increases absorption as compared to apigment alone (composition 4).

FIG. 4 shows the reflectance (total reflection (SCI) and scatteringreflection (SCE)) of compositions 5, 6, 9, 11, and 4 (control) whichwere prepared as shown in Table 2. The figure shows that the addition offumed silica to carbon black causes a decrease in total reflection andscattered reflection.

FIG. 5 shows the absorbance of compositions 5, 6, 9, 11, and 4 (control)which were prepared as shown in Table 2. The figure shows that theaddition of fumed silica to carbon black causes a decrease in totalreflection.

Table 3 summarizes the reflectance and absorbance of all compositionswhich were prepared as shown in Table 2.

TABLE 3 Absorbance and total reflectance of compositions disclosed inTable 2 Average Average L* STDEV L* L* (ref- STDEV L* STD Dev Batch(ref-SCI) (ref-SCI) SCE) (ref-SCE) Absorbance (Abs) 1 20.50 0.69 20.260.62 93.95 0.89 2 21.88 0.92 16.91 1.14 96.41 0.24 3 21.80 0.82 16.941.02 96.49 0.21 4 31.94 0.08 18.68 4.47 92.79 1.04 5 20.30 0.88 14.870.19 96.63 0.20 6 17.92 0.49 14.19 0.44 96.01 1.13 7 16.98 0.28 14.370.47 96.77 0.50 8 16.11 0.22 14.97 0.03 95.05 1.00 9 22.65 1.11 17.721.53 96.06 0.34 10 20.53 0.81 16.49 0.77 96.80 0.16 11 19.89 1.37 15.370.69 95.51 1.55 12 56.63 4.51 54.11 5.64 3.37 5.88 13 66.24 2.64 65.842.67 7.17 4.49

FIGS. 2-5 show that while the efficiency of color chroma and reductionof glossiness is dependent on the nanoparticle loading (wt %) and iseffective for the types of silica tested, the greatest increase inabsorbance was obtained when the silica (nanoparticle) to carbon-black(pigment) ratio is approximately 1.0:1.4.

Table 4 lists properties of three batches of compositions of thisinvention with fumed silica (Degussa Aeroxide LE 3, fumed silica)nanoparticles along with a control batch without any nanoparticles (thefull compositions of which are disclosed in Table 2). Table 4 shows thatthe presence of nanoparticles in a composition enhances the absorbance.In addition, Table 4 shows that as the weight ratio of nanoparticlesplus pigment to film former increases, the percent total reflectancedecreases.

TABLE 4 Absorbance and reflectance of compositions with and withoutfumed silica (Aeroxide LE 3) nanoparticles. Weight % Weight % Weightratio of carbon Weight % KP-550 pigment plus black Aeroxide LE 3 (filmnanoparticles to film % % Total Batch# (pigment) (nanoparticles) former)former Absorbance Reflectance 4 7.14 0 7.14 1.0:1.0 92.8 7.0 (Control) 36.94 2.78 6.94 1.4:1.0 96.5 3.5 5 6.94 5.00 6.94 1.7:1.0 96.6 3.1 6 6.947.00 6.94 2.0:1.0 96.0 2.5

FIG. 6 a shows the absorbance for three (3) systems: 4.00% carbon blackcontrol with no nanoparticles (batch 14), 4.00% carbon black with 4.00%silica shell nanoparticles (batch 15), and 4.00% carbon black with 4.00%fumed silica nanoparticles (batch 16) which were prepared as shown inTable 5. FIG. 6 b shows the luminescence (L*) data for the three systemsin FIG. 6 a. The figures shows that the addition of either 4.00% fumedsilica nanoparticles or 4.00% silica shell nanoparticles results inincreased absorbance and reduced luminescence resulting in enhancedcontrast (darker) in comparison to the carbon black control (nonanoparticles).

TABLE 5 Physical blends of compositions comprising nanoparticles CarbonDegussa Black, Hydrophobic Aeroxide D&C Silica Shells- LE 3 KP-550,Black SH (Kobo Fumed Film IDD, Total Batch # #2 Products) Silica formerSolvent (parts) 14 4.00 0 0 7.00 89.00 100 15 4.00 4.00 0 7.00 85.00 10016 4.00 0 4.00 7.00 85.00 100

Table 6 summarizes the reflectance and absorbance of all compositionswhich were prepared as shown in Table 5.

TABLE 6 Absorbance and total reflectance of compositions disclosed inTable 5 Average L* Average L* Average Trans- Total L* Batch (ref-SCI)(ref-SCE) Absorbance mission (SCI) 14 29.91 3.28 93.73 0.08 6.2 15 27.045.03 94.86 0.03 5.1 16 21.32 2.98 95.15 1.51 3.3

FIG. 7 a shows the total transmission for three (3) systems: 4.00%carbon black control with no nanoparticles (batch 14), 4.00% carbonblack with 4.00% silica shell nanoparticles (batch 15), and 4.00% carbonblack with 4.00% fumed silica nanoparticles (batch 16). FIG. 7 b showsthe total reflectance and scattered reflectance data for the threesystems in FIG. 7 a. The figures show that addition of 4.00% fumedsilica nanoparticles results in increased transmission, reduced totalreflectance and reduced scattered reflectance.

The content of all patents, patent applications, published articles,abstracts, books, reference manuals and abstracts, as cited herein arehereby incorporated by reference in their entireties to more fullydescribe the state of the art to which the invention pertains. Allconcentrations recited in the specification and claims are reported asweight percents, unless otherwise indicated.

It should be understood that the foregoing description is onlyillustrative of the present invention. Various alternatives andmodifications can be devised by those skilled in the art withoutdeparting from the invention. Accordingly, the present invention isintended to embrace all such alternatives, modifications and variationsthat fall within the scope of the appended claims.

1. A composition comprising: (a) a plurality of fumed silicananoparticles, the fumed silica nanoparticles having a particle sizeless than the wavelength of visible light; (b) a combination of ironoxide and carbon black pigments; and (c) a cosmetically orpharmaceutically acceptable carrier comprising one or more of a filmformer or wax; wherein the weight ratio of fumed silica nanoparticles topigment is between about 1.0:1.0 and about 1.0:4.0.
 2. The compositionof claim 1, wherein mean particle size of the iron oxide pigment is inthe range of from about 100 nm to about 2 microns.
 3. The composition ofclaim 1, wherein the fumed silica nanoparticles range in size from about10 nm to about 500 nm.
 4. The composition of claim 1, wherein the fumedsilica nanoparticles range in size from about 100 nm to about 300 nm. 5.The composition of claim 1, wherein the mean particle size of the fumedsilica nanoparticles is about 200 nm.
 6. The composition of claim 1,wherein the weight ratio of silica to pigment is about 1:0 to about 1.3.7. The composition of claim 1, wherein the film former is selected fromthe group consisting of sulfopolyester resins, polyvinylacetate,polyvinyl alcohol polymers, acrylic resins, silicone acrylate polymers,polyvinylpyrrolidones, high molecular weight silicones, organosiloxanes,polyurethanes, and hydrophobic acrylate copolymers or a mixture thereof.8. The composition of claim 1, wherein the film former is siliconeacrylate copolymer.